近年來，動態網頁的興起，使得伺服器之工作量增加，快取伺服器通常把動態產生的網頁設定成不快取，為了要得到即時的網頁，用戶端每次都需要把請求送到網頁伺服器。並且隨著無線網路的蓬勃發展，越來越多人透過行動裝置取得動態網頁，因為行動裝置電源的限制，在行動裝置端快取動態網頁變的越來越重要了。為了要減少網頁伺服器的工作量還有節省客戶端行動裝置的能源，我們提出了一些方法來解決這個問題。

　　首先，我們提出可以把動態網頁暫存於網頁伺服器端的架構，並且在資料庫資料變更時，可以找出過期的快取網頁。再來，在廣播無效驗證的機制下，我們利用Bloom filter讓伺服器可以把過期的網頁告知行動裝置。最後，在stateful伺服器的架構下，伺服器只需要紀錄網頁在更新之後有無使用者存取，這樣可以有效減少無效驗證的廣播量。實驗證明，TimeStamp 或UIR演算法在結合我們的方法後，都可以節省40%的無效驗證廣播量，甚至比Perfect Server的效能更好。

　　In recent years, it has been a common practice to deploy the dynamic web applications for providing web services. Dynamic web applications increase server loads. Cache proxies are usually configured to disable caching the dynamic pages because they are generated dynamically. Clients must send requests to the servers for obtaining the fresh dynamic pages. But these dynamic pages may not change every time they are accessed. Also, more people use mobile devices to get dynamic web pages in the wireless network. Caching dynamic pages on the mobile clients becomes very important due to the power constraint of mobile devices. In order to reduce server workload and mobile clients’ power consumption, power-aware methods are proposed to overcome this problem.

　　First, we introduce a framework to cache dynamic pages on the server side and to invalidate stale pages when data on the underlying database changes. Second, based on the Invalidation Reports approach, we propose to use Bloom filter to indicate which pages on the server side are stale for the mobile clients. Finally, we propose a stateful approach, which only counts the number of queries after updates to reduce the IR timestamp size. The conducted experiments show that our proposed approach combined with the Timestamp or UIR algorithms can reduce around 40% of the IR size. Also, our method performs better than the Perfect Server that has the full knowledge of the content of the entire mobile client’s cache in terms of transmitted IR size.

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